PROSOBRANCHIATA. 349 
vel reticulatis tenuissimis ornatd; aperturd semilunari ; columelld arcuatd, in medio 
denticulata. 
Diameter, 33;ths of an inch. 
Locality. UWeadon Hill (8S. Wood). 
This is a fossil of which I have myself found several specimens at the above locality. 
It resembles JV. apyerta in outward form, its most material difference consisting in its 
having six or seven very distinct ridges or carinule not quite equidistant, and some- 
what rounded, but these the artist has unfortunately not sufficiently shown m the figure. 
No one, however, on comparing specimens with those of aperta, would fail to perceive 
these carinule. 
No. 273. Nerivina puanunata, F. 2. Hdwards, MS. Tab. XXXIV, fig. 21 a, 6. 
NERETINA PLANULATA, J. Lowry. Chart Brit. Tert. Foss., pl. iti, 1866. 
_ = Sandberger. Land- und Siissw.-Conch., p. 2638, t. xv, fig. 14, 
1872, 
Spec. Char. “ Testd globosd, apice obtuso, paulo eroso. Aunfractus tres infra suturas 
tenuissimas subimpressi, ceterum convent, nitidi, flavidi, guttulis albis equoliter conspersis 
aut seriatim depositis variegati; ultimus ceteris omnibus quadrato altior, Apertura 
paulo obliqua semilunari, margine dextro et basali tenui, acuto, pariete et columella callo 
nitido, leviter concavo, intus medida parte plicd supremd maxima et duodecim minoribus 
obtusis munito obtectis. Operculum semitunare, inferné apophysibus duabus arcuatis 
discrepantibus armatum.”—Sandberger. 
Height, ~sths of an inch. 
Locality. Weadon Hill (Hdwards). 
A very determinable figure is given of a shell under the above name by Mr. Lowry, 
who tells me it is a MS. name given by Mr. Edwards. This has been figured and 
described also by Sandberger from a specimen sent to him by Mr. Edwards. Our shell 
is prettily ornamented with diagonal and dark wavy lines. I have not the species. 
Genus 33rd.—Nerita. Adanson. 
For generic characters see anfé, p. 342. 
No. 274. Neriva tricartnata, Lamarck. Tab. XXXIV, fig. 22 a, 4. 
NerITA TRICARINATA, Lamk. Ann. du Mus., tom. viii, pl. Ixii, fig. 4 a, 6, 1806. 
— — Desh. Coq. foss. des Eny. de Par., t. ii, p. 160, 1824. 
